This application guide is the first of a series which aims to explain how the Soundcraft Vi series handles MADI audio
channels, clocking, redundancy and control so that users can best understand how to manipulate the protocol to
expand their systems. It also covers the various option cards and connection options available.
Soundcraft Vi Series MADI Fundamentals
What is MADI?
Multichannel Audio Digital Interface, MADI or AES10 is an Audio Engineering Society (AES) standard electronic
communications protocol that defines the data format and electrical characteristics of an interface that carries
multiple channels of digital audio. The AES first documented the MADI standard in AES10-1991, and updated it in
AES10-2003 and AES10-2008. The MADI standard includes a bit-level description and has features in common with
the two-channel format of AES3. It supports serial digital transmission over coaxial cable or fibre optic lines of 28,
56, or 64 channels; and sampling rates of up to 96 kHz with resolution of up to 24 bits per channel.
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MADI and Vi
The Vi series primarily uses MADI to send 64 channels of bi-directional audio between consoles and peripheral
devices such as 3rd party recording devices or Soundcraft's own range of stage boxes.
Connection Basics - The connection type is either optic or CAT5 (further information about the cables & connectors
is toward the end of this document). You will notice that, with the optical versions of the MADI cards, there is an
'IN' & 'OUT' for both the 'MAIN' & 'AUX' connection. This is due to there being a separate MADI link in both
directions for bi-directional communication (to and from the device). These two MADI links are combined on the
CAT5 versions.
Clocking Basics - Clock information is sent from sender to receiver which, in a basic point to point system, means
that the peripheral device can simply clock to its incoming MADI stream. This allows that peripheral device to
distribute the master console clock (from the console) to all of its internal cards (such as the A-D converters in a mic
card).
Control/Status Basics - A key feature of MADI is that serial data transmission is possible. Soundcraft uses this serial
link to send and receive control & status information to & from the range of Soundcraft stage boxes.
The control information (sent from console to stage box) includes the head amp gain control, phantom power
(+48v) & HPF (high pass filter) of the individual microphone cards loaded into a stage box.
The status information (sent from stage box to console) first tells the console which stage box type is connected,
which cards are loaded into the various slots in the stage box (microphone input cards, AES/EBU I/O cards, output
cards etc) and lets the console know the health status of the stage box such as 'PSU1/2 active', 'MAIN/AUX MADI
connection valid', 'Fan/Temperature', 'discovered cards active' etc... Any errors will be reported on screen (in red).
The operator can also access this status information from the consoles 'system' menu.
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MADI Wikipedia webpage - http://en.wikipedia.org/wiki/MADI